@Good_Oatmeal
I'll make a patch regarding the lack of certain resources because I think that request is reasonable with the total lack of other asteroids. I don't plan on supporting this experimental mod for long as I want to move to new projects (I'm already working on 1 new mod with plans for at least 1 more past that and I don't want this experimental project to eat much more of my time tbh. I barely have time to actually play this game as it is). You can go into the workshop directory and adjust the droprates as I probably won't be updating this mod anymore after I've updated it to 1.0.1.

This was an interesting experiment, but it's time I move on.

@Good_Oatmeal
You didn't find any diamonds?

Yes the spawn ratios are that more rare resources drop more rarely. I found that if I set the rarer materials to drop more often, I could basically sell CPUs all day for too easy credits and I want mining to be profitable, yet still requiring some effort.
The ratios are similar to the one in Mineable Megaroids, yet all resources spawn in the dwarf planet (and you get a few diamonds and a little bit of hyperium as a bonus).
I made hyperium spawn so infrequently because so little is needed, but with the lack of hyperium asteroids witht his particular mod, the only realistic way to get more hyperium would be to buy it from dead enemies, from space stations and from trade ships.

Regarding the hyperium disappearing, this should not be a thing. This mod doesn't affect things like that, so I don't know what the issue could be except that the hyperium perhaps goes straight into your hyperdrives?

@Good_Oatmeal
Making it bigger I tended to end up with 'asteroids' larger than the sun :P
I think it would be better to make a total conversion for something like this, but I do admit that the idea of a tiny little spaceship mining through seemingly endless tunnel system does is somewhat appealing to me ...but I don't know if something like that can be done without making it a total conversion and TCs are a whole new level of magnitude concerning the effort required to make it, test it and keep it updated.

@Good_Oatmeal
Before I uploaded my Mineable Dwarf Planets, I thoroughly tested droprates and the droprates of a single dwarf planet are roughly equal to at least 15 mineable megaroids from my Mineable Megaroids mod and that is already quite a lot.
I don't think you need to worry about resources running out. There are iirc several mods with which you can increase galaxy sizes (up to 1030 star system, meaning 5000+ mineable dwarf planets).

Regarding the bigger planets, I've also tested this and while I can make these asteroids basically as big as I want to, graphics will become noticeably more stretched out. I'd at the very least would want to make new pixelart for the resource nodes (which would also need a normal map).